Be skilled in controlling POTASSIUM levels for patients with heart failure

Hypokalemia and hyperkalemia are common electrolyte disorders caused by changes in potassium intake, altered excretion, or transcellular shifts....
Mahitab Hany, BS Pharm, PGDipClinPharm, PGDipClinNutrition

Overview

Getting POTASSIUM levels right for patients with heart failure can be a balancing act due to changes in medications, diet and kidney function. Hypokalemia and hyperkalemia are common electrolyte disorders caused by changes in potassium intake, altered excretion, or transcellular shifts. Diuretic use and gastrointestinal losses are common causes of hypokalemia, while kidney disease, hyperglycemia, and medication use are common causes of hyperkalemia.

Low (HYPOkalemia) or high (HYPERkalemia) potassium levels increase risk of arrhythmias. And patients with heart failure seem to have a higher risk of death as potassium levels fall below 4 mEq/L or rise above 5.5 mEq/L.

NPS-adv

Management

Mild hypokalemia

First optimize doses of heart failure medications that raise potassium, such as an ACEI, ARB, or spironolactone. If that’s not enough, rely on prescribing potassium chloride as the go-to salt form to replace potassium AND chloride loss from diuretics. Fine-tune potassium supplementation based on diuretic dose, baseline potassium, kidney function and other medications. Think of potassium chloride 20 mEq/day as a starting dose to prevent hypokalemia while on a loop diuretic.

In general, check electrolytes about weekly until stable then every 3 or 4 months. Also check magnesium levels and supplement if needed since magnesium is required for potassium uptake. Plan ahead for changes that may affect the potassium dose. For example, if the diuretic dose is doubled for a few days, consider also “boosting” the usual potassium dose by 40 to 80 mEq/day.

Mild hyperkalemia

Reduce potassium doses and limit dietary potassium (salt substitutes, etc) and avoid NSAIDs, TMP/SMX, and most other medications that raise potassium. Then think about adding or increasing the dose of a loop diuretic if volume status and blood pressure allow. If necessary, step down the spironolactone dose then reduce the ACEI, ARB or Entresto (sacubitril/valsartan) dose. But try to avoid stopping these medications. If needed, evaluate whether to add a potassium binder after weighing costs, side effects, etc. Consider Veltassa (patiromer) first, Lokelma (sodium zirconium cyclosilicate) or Resinokaten (calcium polystyrene sulfonate) can cause edema. Both Veltassa and Lokelma are NOT available while Resinokaten is available in Egypt.

References

  1. Viera AJ, Wouk N. Potassium Disorders: Hypokalemia and Hyperkalemia. Am Fam Physician. 2015 Sep 15;92(6):487-95.
  2. Ferreira JP, Butler J, Rossignol P, Pitt B, Anker SD, Kosiborod M, Lund LH, Bakris GL, Weir MR, Zannad F. Abnormalities of Potassium in Heart Failure: JACC State-of-the-Art Review. J Am Coll Cardiol. 2020 Jun 9;75(22):2836-2850.
  3. Cooper LB, Benson L, et al. Association between potassium level and outcomes in heart failure with reduced ejection fraction: a cohort study from the Swedish Heart Failure Registry. Eur J Heart Fail. 2020 Aug;22(8):1390-1398.